Effects of Acremonium coenophialum Infestation, Bermudagrass, and Nitrogen or Clover on Steers Grazing Tall Fescue Pastures

Abstract

Performance of cattle grazing tall fescue (Festuca arundinacea Schreb.) is depressed when the grass is infested (E+) with the endophytic fungus Acremonium coenophialum Morgan‐Jones and Gams. Steer performance can be improved when clover (Trifolium spp. L.) is overseeded into tall fescue pastures, and beef production/acre can be increased when bermudagrass [Cynodon dactlyon (L.) Pers.] is grown in combination with tall fescue. The objective of this study was to compare effects on steer performance of including ladino clover (T. repens L.), ‘Midland’ bermudagrass, or a combination of both in E+ and noninfested (E−) tall fescue pastures. Three tester steers (Bos taurus L.) per pasture grazed between April and September from 1983 through 1985. Additional cattle were used in a modified put‐and‐take management system to maintain similar quantity and quality of forage among pastures. Forage growth and consumption were measured by cage‐and‐strip methodology. Pastures with bermudagrass treatments averaged 18 and 53% bermudagrass in spring and summer, respectively. Clover content of pastures overseeded with clover was variable among treatment combinations and years and ranged from 6 to 53%. Greater average daily gains (ADG), beef production per acre, and forage dry matter consumption, and lower rectal temperatures and hair coat scores, were observed when cattle grazed E− rather than E+ tall fescue. Steer ADG was higher on E+ pastures when bermudagrass was present. Clover was equally effective in increasing ADG on E+ and E − tall fescue pastures. Bermudagrass and clover were both effective in improving steer performance and/or production on both E+ and E− tall fescue. Additionally, bermudagrass reduced somewhat the detrimental effects of E+ tall fescue.

Nodulation and root growth of forage legumes sown into tall fescue swards

“…are often deleterious to livestock performance because of toxins produced by association with the endophyte, Neotyphodium coenophialum (Morgan-Jones and Gams) Glenn, Bacon and Hanlin comb. nov. One means for overcoming this problem is to include legumes (Hoveland et al, 1981;Coffey et al, 1990;McMurphy et al, 1990;Chestnut et al, 1991) in the sward. However, introducing legumes into tall fescue swards is difficult, particularly in well-established and endophyte-infected stands (Fribourg et al, 1978;Luu et al, 1982).…”

Fescue toxicosis and its influence on the rumen microbiome: mitigation of production losses through clover isoflavones

“…provide nitrogen fixation to the plant. In addition to benefitting both the bacterium and soil by this nitrogen fixation property, legumes are high in digestible nutrients and protein, increasing the quality of the pasture when included alongside grasses (Chestnut et al 1991;Duranti and Gius 1997). When conducting a study with sheep, Thornton and Minson calculated voluntary intake of legumes was 28% higher when compared to equally digestible grasses (1973).…”

“…In particular, red and white clover have proven to be most successful at increasing growth and overall gains and mitigating fescue toxicosis (McLaren et al 1983;Lusby et al 1990;Chestnut et al 1991;Beck et al 2012). Lusby et al (1990) found that the inclusion of red clover into stands of tall fescue not only reduced the severity of fescue toxicosis (reduced rectal temperatures and respiration rates) but it improved average daily gain and carcass quality compared to cattle on tall fescue alone.…”

Legume establishment and persistence at sites varying in landscape position, grazing method, and soil characteristics

“…were also greater in Tennessee in endophyte free and endophyte infected tall fescue pastures overseeded with red clover than in pure stands of either tall fescue type (Chestnut et al, 1991). Crude protein percentages were greater in tall fescue and orchardgrass pastures mixed with legumes than in nitrogen fertilized bermudagrass…”